When using the stadia method (the plotting of points) of making a topographical contour map, engineers and surveyors have experienced difficulty in precisely drawing the lines or contours necessary to provide an accurate display of the topography of a finite parcel of land. In particular, the topographical lines are drawn based on a series of points plotted in generally a minimum of three directions. The plotted points each represent a certain elevational unit or elevation (e.g. 1 foot). Interpolation is necessary to precisely position the contour lines, especially when the total elevation requires a fraction of a unit. Although certain devices have been developed for the purpose of addressing the problem, the prior art devices are generally expensive, bulky, and difficult to use.
It would be of significant advance in the art of producing topographical contour maps to develop a device having a durable, compact construction and design which facilitates the positioning of points to enable the drawing of accurate, low-cost topographical contour maps.